had flourished in this overgrown forest. who built this city ? in the ruined cities of egypt, the stranger knows the story of the people whose vestiges are around him. america, say the historians, was peopled by savages. but savages never reared these structures, never carved these stones. we asked the indians who made them ? and their answer was "quien sabe ?" -- who knows ? during the next century, other explorers revealed the amazing variety of new-world civilizations. a great city, teotihuacan, dominated the basin of mexico. atop a hill in the valley of oaxaca, sits monte alban, the royal center of a mighty kingdom. and in the forests and jungles of guatemala, maya city states once reigned over thousands of square miles.